12. The Decline Picks Up the Pace: Ptolemy V
When Ptolemy IV died in 204 BC, his son and heir, Ptolemy V (210 – 181 BC), was too young to rule in his own right. Power was thus supposed to go to the child king’s mother/ aunt, Arsinoe III, who was to rule as regent. However, that arrangement went awry, when some of the former king’s courtiers, who had gotten used to dominating the weak willed Ptolemy IV, feared that they would lose their influence, and perhaps their lives, if Arsinoe assumed power. So they beat her to the punch by murdering her, and taking the regency for themselves.
The new regents were murdered soon thereafter, one of them lynched on the street by an Alexandrian mob, and Egypt grew increasingly unstable. The other Hellenistic kingdoms took advantage of the chaos along the Nile, and the Seleucids and Macedonians made a pact to divvy up the Ptolemaic Kingdom. The dynasty probably would have come to an inglorious end during the reign of Ptolemy V, if not for the intervention of a rising power from the other side of the Mediterranean: Rome.